Cascades Volcano Observatory's mission
The U.S. Geological Survey's Cascades Volcano Observatory strives to serve
the national interest by helping people to live knowledgeably and safely
with volcanoes in WA, OR, and ID.

Oregon's Newberry Volcano is the largest volcano in the Cascade Range and covers an area the size of Rhode Island (about 3100 km2 or 1200 mi2). Unlike familiar cone-shaped Cascade volcanoes, Newberry was built into the shape of a broad shield by repeated eruptions of mostly fluid lava over the past 400,000 years. Between the lava-producing eruptions the volcano has erupted explosively. The most recent eruption, about 1,300 years ago, was explosive and ended with the extrusion of the Big Obsidian Flow within the volcanic caldera.
This new poster of Newberry Volcano uses LiDAR (light detection and ranging) technology to reveal previously unseen detail in the volcano's youngest lava flows and vents—the Lava Butte cinder cone, Newberry's northwest rift zone, Central Pumice Cone and The Big Obsidian Flow.
Download the poster Newberry Volcano's Youngest Lava Flows to see more.

Crews from the USGS-Cascades Volcano Observatory return from working with the Alaska Volcano Observatory, Plate Boundary Observatory, and IRIS' Transportable Array to repair, refurbish and rebuild volcano monitoring stations in Alaska, including the installation of a new volcanic gas monitoring site at the summit of Augustine. The station is similar to the SNIF monitoring station that currently operates in the crater of Mount St. Helens. Visit the Alaska Volcano Observatory to see volcano updates and recent images of fieldwork.
Read about volcanic gas monitoring at Mount St. Helens and view a month's worth of monitoring data by clicking on Mount St. Helens Monitoring and zooming into the crater to find station SNIF on the interactive map.

CVO scientists work with rangers and volunteers to interpret local geology.June 22, 2015

Research geologist Carl Thornber leads a group of Mount St. Helens National Volcanic Monument interpretive rangers and volunteers along the boardwalk at the Trail of Two Forests, explaining the formation of lava tubes and tree molds. The longest lava flow at Mount St. Helens is the 1900-year-old Cave Basalt Flow, erupted from a vent on the south flank of the volcano which traveled 11 km (~7 miles) downslope to the Lewis River. Many flow features are still visible including the Ape Cave lava tube. This pahoehoe flow is similar in composition, size and physical character to tube-fed lava flows that are currently active at Kīlauea Volcano, Hawaii.
Plan a visit to the Ape Cave Interpretive Site to learn more about the Pre-1980 Eruptive History of Mount St. Helens, Washington.
Visit the Hawaii Volcano Observatory for images and information about Kīlauea.